Oxidant, dominant, carbon combustion

The tropospheric chemistry of carbon compounds is summarized in Figure 5. CH4 is the dominant input of reactive carbon in the atmosphere, and the main action of atmospheric chemistry is to oxidize it to C02. Atmospheric H2C=0 and CO are produced along the way. Combustion is only a small source of CO, and the total CH contribution to atmospheric carbon is less than 1% of the atmospheric carbon exchanged by the C02 cycle. The contribution of reactive hydrocarbons such as terpenes is not clear, although they may provide a significant source of CO and... 

Coal combustion releases substantial quantities of carbon dioxide (CO2) to the atmosphere that can participate in one or more of the various cycles that exist in the biosphere and atmosphere (Clark, 1989 Graedel and Crutzen, 1989 Frosch and Gallopoulos, 1989 Maurits la Rivibre, 1989 Schneider, 1989 Speight and Lee, 2000) have dominated the global environmental system for millennia. In addition, other coal plant emissions such as sulfur dioxide (SO2) and nitrogen oxides (NO) are major contributors to acid rain (Manowitz and Lipfert, 1990). 

While partial oxidation of the fuel is the desired target reaction in this scheme, a range of reaction selectivities is typically observed as a function of temperature, gas-phase concentrations, carrier conversirai, and hence time and/or location within the reactor. For instance, full combustion of the fuel (R22) can be expected to dominate initially when a large amount of lattice oxygen is available, while partial combustion (R21) begins to dominate as this carrier becomes reduced and oxygen availability is lower. As oxygen availability decreases further, carbon deposition... 

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